From: Adam Brickman Adam.Brickman@cirrus.com

A call to wm_adsp_write_ctl() could cause a kernel crash if it does not retrieve a valid kcontrol from snd_soc_card_get_kcontrol(). This can happen due to a missing control name prefix. Then, snd_ctl_notify() crashes when it tries to use the id field.

Modified wm_adsp_write_ctl() to incorporate the name_prefix (if applicable) such that it is able to retrieve a valid id field from the kcontrol once the platform has booted.

Fixes: eb65ccdb0836 ("ASoC: wm_adsp: Expose mixer control API") Signed-off-by: Adam Brickman Adam.Brickman@cirrus.com Signed-off-by: Charles Keepax ckeepax@opensource.cirrus.com --- sound/soc/codecs/wm_adsp.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c index 410cca57da52d..344bd2c33bea1 100644 --- a/sound/soc/codecs/wm_adsp.c +++ b/sound/soc/codecs/wm_adsp.c @@ -2049,6 +2049,7 @@ int wm_adsp_write_ctl(struct wm_adsp *dsp, const char *name, int type, { struct wm_coeff_ctl *ctl; struct snd_kcontrol *kcontrol; + char ctl_name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN]; int ret;

ctl = wm_adsp_get_ctl(dsp, name, type, alg); @@ -2059,8 +2060,25 @@ int wm_adsp_write_ctl(struct wm_adsp *dsp, const char *name, int type, return -EINVAL;

ret = wm_coeff_write_ctrl(ctl, buf, len); + if (ret) + return ret; + + if (ctl->flags & WMFW_CTL_FLAG_SYS) + return 0; + + if (dsp->component->name_prefix) + snprintf(ctl_name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN, "%s %s", + dsp->component->name_prefix, ctl->name); + else + snprintf(ctl_name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN, "%s", + ctl->name); + + kcontrol = snd_soc_card_get_kcontrol(dsp->component->card, ctl_name); + if (!kcontrol) { + adsp_err(dsp, "Can't find kcontrol %s\n", ctl_name); + return -EINVAL; + }

- kcontrol = snd_soc_card_get_kcontrol(dsp->component->card, ctl->name); snd_ctl_notify(dsp->component->card->snd_card, SNDRV_CTL_EVENT_MASK_VALUE, &kcontrol->id);